The chemical industry uses steam taps and steam guns for saturated steam up to a maximum temperature of 200.degree. C. However, there is also a need for water/steam mixing and an apparatus producing such a mixture from the individual components water and steam, which can then be applied by means of a gun. Such a water and steam mixture must have a temperature of 200.degree. C. at the most. At higher temperatures than 200.degree. C. there is a risk that the supply hoses will tear and that local overheatings or burning will occur.
It is therefore an object of the invention to provide a water and steam mixing device which ensures that the mixture never exceeds a given temperature, such as approximately 200.degree. C.